function?varargout?=?kreisDemod（varargin）

%KREISDEMOD?Fringe?pattern?demodulation?method?from?two?phase-shifted
%interferograms?using?the?Kreis?method?[1]
%
%?Usage:?[pwMod]?=?kreisDemod（I1I2Mask）
%
%?Inputs:
%
%???I1??[NRows?x?NCols]?Image?map?with?NRows?and?NCols?the?number?of?rows
%???????and?columns?of?the?fringe?pattern
%???Mask?[NRows?x?NCols]?Processing?mask
%
%?Outputs:
%???pw??[NRows?x?NCols]??Wrapped?modulating?phase.
%
%???Javier?Vargas
%???06/06/2011
%???copyright?@2011
%???Biocomputing?Unit?Centro?Nacional?de?Biotecnolog?a?（CSIC）
%???http://biocomp.cnb.csic.es/
%???$?Revision:?1.0.0.0?$
%???$?Date:?25/10/10?$
%???$?Revision:?1.0.0.0?$
%???$?Date:?06/06/11?$
%
%?THIS?CODE?IS?GIVEN?WITHOUT?ANY?GUARANTY?AND?WITHOUT?ANY?SUPPORT
%
%?REFERENCES
%
%[1]?T.?M.?Kreis?P.?P?Jueptner?“Fourier?transform?evaluation?of?
%????interference?patterns:?demodulation?and?sign?ambiguity“?Proc?of?SPIE
%????vol.?1553?（1992）

try
????
????I1?=?varargin{1};
????I2?=?varargin{2};
????
????if?（length（varargin）?????????Mask?=?ones（size（I1））?>?0.5;
????en